The present invention relates in general to tamper-evident enclosures which are intended to enclose a connection or object so as to prevent tampering with that connection or object or at least provide a visual indication of any tampering attempt. More specifically the present invention pertains to a unitary, molded plastic, tamper-evident clam-shell cover which has a self-locking feature and which utilizes living hinges.
In a variety of industrial situations there is a desire if not a need to maintain the integrity of a seal, connection, fitting, valve, joint, etc. It may be important to know that a particular connection has not been tampered with, such as loosening a mechanical or electrical connection or opening a flow line. Tamper-evident covers may be used to discourage thefts as well as tampering attempts. Even if a tampering attempt is successful, the tamper-evident feature puts the end user on notice of such an attempt which may ultimately prevent a more serious problem from occurring. If the user is alerted to a tampering attempt, whether successful or not, then steps can be taken by the user to check the connection and verify whether or not the attempt was successful.
Some typical situations which may benefit from tamper-evident covers of tile type being generally discussed herein include a seal (cover) for a gas meter coupling nut, a seal for a pipe coupling and a cover for wellhead distribution valving. Examples of these and related situations which may benefit from tamper-evident cover are described and illustrated by the following listed patent references:
______________________________________ Patent No. Patentee Issue Date ______________________________________ 4,326,740 Guiler Apr. 27, 1982 4,372,593 Kesselman Feb. 8, 1983 4,405,161 Young et al. Sep. 20, 1983 4,471,982 Nielsen, Jr. Sep. 18, 1984 4,552,394 Kesselman Nov. 12, 1985 4,600,220 Agnelli Jul. 15, 1986 4,664,432 Swift May 12, 1987 ______________________________________
The tamper-evident, self-locking cover of the present invention is designed primarily for mechanical and electrical connections. These types of connections may include hydraulic as well as pneumatic lines and plumbing fittings. The electrical connections may take on a variety of shapes and uses. Structurally the type of situation which lends itself to being protected by the present invention is where a larger control member or connection is assembled to at least one, but often two smaller incoming lines, conduits or pipes. These incoming lines, conduits, or pipes may connect to the central member from the same side or from opposite sides. And as will be explained hereinafter, the specific design of the self-locking cover of the present invention contemplates such variations.
The cover of the present invention is designed with living hinges which close the two clam shell halves around the smaller lines on either or both sides of the larger central member and completely encases the central member. By means of a snap-fit, self-locking structure utilizing a tamper-evident technique, it is not thereafter possible to gain access to the larger central member or to the points of connection to the incoming lines, conduits or pipes, whatever this larger central member might be, without damaging the cover or fracturing some portion of the cover or the snap-fit assembly which would thus reveal a tampering attempt.
While the cover of the present invention could simply be destroyed and thereby permit access to the central member, mere access is generally not the issue. If the end user understands that the connection, object or central member has been tampered with or vandalized, appropriate steps can be taken to investigate the matter and correct the problem before utilizing that central member in a way that could cause more serious damage or injury. The issue here is not a matter of the end user being able to deal with the problem of vandalism or other damage after it has occurred. The issue is being able to determine in advance whether or not vandalism, tampering or sabotage has occurred or may have occurred. If the cover has been destroyed, early detection is a certainty. If the proper end user is aware of a tampering attempt then steps can be taken to check the connection (central member) and see if everything is in order and if not, provide the necessary repairs or replacement of damaged or removed parts.